Mineralogy and Geochemistry Characteristics of Tanjero Formation in Selected Locations, Northeast of Iraq

Abstract

Tanjero Formation (belongs to the upper cretaceous sequences( which are exposed in the northeast part of Iraq within the high folded zone. In this study, the mineralogy and geochemistry of the formation are examined by XRD and XRF techniques. The mineralogical study reveals that Calcite is the main mineral making the carbonate rocks of the formation with subordinate minerals of quartz and a low quantity of clay minerals (Chlorite, montmorillonite, and illite). Geochemical results revealed high levels of silica and calcium, aluminum, magnesium, and iron oxides. High concentrations of some trace elements (Cr, V) reflect their origin of basic and ultrabasic igneous rocks. The high content of Mn in the carbonate rocks of the formation reflects the depositional environment which is a deep marine environment. Most trace elements in the present study have positive correlations with SiO2, Al2O3, and K2O suggesting their association with clay minerals.